Determination device and determination method

Abstract

There is provided a determination device comprising a determination section configured to determine a direction of a position of an external device on a basis of a synthetic radio wave obtained by combining a first radio wave and a second radio wave, the first radio wave being transmitted from the external device and received by a first antenna, the second radio wave being transmitted from the external device and received by a second antenna, wherein delay between the first radio wave and the second radio wave is designed to be about ¼ wavelength before generating the synthetic radio wave, and the second radio wave is further delayed by about ½ wavelength.

What is claimed is: 
     
         1 . A determination device comprising
 a determination section configured to determine a direction of a position of an external device on a basis of a synthetic radio wave obtained by combining a first radio wave and a second radio wave, the first radio wave being transmitted from the external device and received by a first antenna, the second radio wave being transmitted from the external device and received by a second antenna,   wherein delay between the first radio wave and the second radio wave is designed to be about ¼ wavelength before generating the synthetic radio wave, and the second radio wave is further delayed by about ½ wavelength.   
     
     
         2 . The determination device according to  claim 1 ,
 wherein, by adjusting at least a distance between the first antenna and the second antenna, the delay between the first radio wave and the second radio wave is designed to be about ¼ wavelength before generating the synthetic radio wave.   
     
     
         3 . The determination device according to  claim 1 ,
 wherein, on a basis of the synthetic radio wave, the determination section determines whether the external device is positioned in a direction along a first axis connecting the first antenna to the second antenna or a direction along a second axis perpendicular to the first axis.   
     
     
         4 . The determination device according to  claim 3 ,
 wherein the determination section determines that the external device is positioned in the direction along the second axis in a case where the synthetic radio wave has a wave height that falls below a designated wave height.   
     
     
         5 . The determination device according to  claim 1 , wherein
 the first antenna and the second antenna are disposed on a ceiling of a vehicle, and   the determination section determines whether the external device is positioned inside or outside a vehicle cabin of the vehicle on a basis of the synthetic radio wave.   
     
     
         6 . The determination device according to  claim 1 , wherein
 the second radio wave is further delayed by about ¼ wavelength, and   on a basis of the synthetic radio wave, the determination section determines whether the external device is positioned on the first antenna side or on the second antenna side along a first axis connecting the first antenna to the second antenna.   
     
     
         7 . The determination device according to  claim 6 ,
 wherein the determination section determines that the external device is positioned on the second antenna side along the first axis in a case where the synthetic radio wave has a wave height that falls below a designated wave height.   
     
     
         8 . The determination device according to  claim 6 , wherein
 the first antenna is disposed inside a room,   the second antenna is disposed outside the room, and   the determination section determines whether the external device is positioned inside or outside the room on a basis of the synthetic radio wave.   
     
     
         9 . The determination device according to  claim 1 , further comprising
 a synthesis circuit configured to generate the synthetic radio wave.   
     
     
         10 . The determination device according to  claim 1 , further comprising:
 the first antenna; and   the second antenna.   
     
     
         11 . The determination device according to  claim 1 , further comprising:
 a first wave height adjustment circuit configured to adjust wave height of the first radio wave to a designated wave height; and   a second wave height adjustment circuit configured to adjust wave height of the second radio wave to a designated wave height.   
     
     
         12 . A determination method comprising
 determining a direction of a position of an external device on a basis of a synthetic radio wave obtained by combining a first radio wave and a second radio wave, the first radio wave being transmitted from an external device and received by a first antenna, the second radio wave being transmitted from the external device and received by a second antenna,   wherein delay between the first radio wave and the second radio wave is designed to be about ¼ wavelength before generating the synthetic radio wave, and the second radio wave is further delayed by about ½ wavelength.